President Joseph Kabila at a parade marking the 50th anniversary of the Democratic Republic of Congo's independence. Photograph: Mark Renders/Getty Images

"Fabulous minerals. Magnificent music. Great cuisine. A landscape that stretches from lush rain forest to Swiss-looking mountains. And a people still mired in violence and misery a half century after independence from Belgium." This was the take of the Associated Press on the 50th anniversary celebrations in the Democratic Republic of Congo last week. A total of 18 African presidents, including Zimbabwe's Robert Mugabe, watched a parade of 15,000 soldiers and 400 tanks and heard Congo's leader, Joseph Kabila, call for a "moral revolution". Other guests included Ban Ki-moon, the UN secretary general, but the biggest talking point was the presence of Belgium's King Albert II.

The rape and plunder of Congo under his ancestor, Leopold II, remains one of history's greatest crimes. Last week's milestone reignited debate over the legacy of colonialism in Africa and whether, even half a century later, all the continent's ills can still be hung around its neck. Under Leopold's brutal regime, as many as 10 million were killed, according to some estimates. An outcry over the mass slaughter forced him to surrender the country in 1908 to the Belgian government.

When independence finally came in 1960, the country entered a new nightmare. Not unlike other former colonial masters, Belgium continued to meddle and was blamed, along with the CIA, for the 1961 assassination of Patrice Lumumba, Congo's first democratically elected prime minister. Both Belgium and the US then supported the 32-year dictatorship of Mobutu Sese Seko, a pro-Western leader seen as a bulwark against communism. He robbed his people of an estimated $5bn and made corruption a political way of life.

Mobutu was finally overthrown in 1997, but then came a war that sucked in six neighbouring countries and left at least 4 million dead, mainly from strife-driven hunger and disease.

The world's biggest UN peacekeeping force has been in Congo for more than a decade but some 45,000 people are still dying each month, according to the International Rescue Committee, mainly from hunger and disease.

Mwahila Tshiyembe, director of the Pan-African Institute for Geopolitics in Nancy, France, said the Belgians were not solely to blame for Congo's woes. Congo's leaders since independence have been marked by corruption and bad governance and have needlessly sought to blame their former coloniser, he told AP.

Alexis Thambwe Mwamba, Congo's foreign minister, now seems ready to end the blame game. "Fifty years later, we cannot say that if things are not going well in Congo, it's the fault of Belgium or of Leopold II."

Not everyone is ready to draw a line under the past, however. Patrice Lumumba's three sons announced this month they would bring a private prosecution against 12 living Belgians allegedly involved in the abduction, torture and murder of their father in 1961.